Assessment of the Cerebral Perfusion During the Period of Deep Hypothermia at 18°C in Patient Undergoing Pulmonary Endarterectomy Surgery.

Pulmonary Hypertension Clinical Trial

— HYPO-TEP  

Official title:

Assessment of the Cerebral Perfusion During the Period of Deep Hypothermia at 18°C in Patient Undergoing Pulmonary Endarterectomy Surgery.

Clinical Trial Details — Status: Recruiting

Administrative data

• NCT number: NCT06250374
• Other study ID #: 2023-A00270-45
• Status: Recruiting
• Phase: N/A
• Start date: August 24, 2023
• Est. completion date: May 24, 2025

Study information

• Verified date: August 2023
• Source: Fondation Hôpital Saint-Joseph
• Contact: Sylvain DIOP, Dr
• Phone: +33140948637
• Email: sdiop[@]ghpsj.fr
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

Cardiopulmonary bypass (CPB) surgery present risk of acute postoperative neurological complications. These complications are most often postoperative cognitive dysfunction (confusion, cognitive disorders, executive disorders) with a prevalence of up to 40% at 5 years, and ischemic (stroke) with an incidence of between 0.4 and 14%. The causes are usually multifactorial, but altered cerebral perfusion during CPB surgery is an important prognostic factor. Data regarding the effect of deep hypothermia on cerebral perfusion during CPB in adult are scarce. Currently, aortic arch replacement following aortic dissection or aneurysm, and pulmonary artery endarterectomy (PAE) in the treatment of pulmonary hypertension of post embolic origin are performed under deep hypothermia.

In this latter indication, the need to obtain a completely bloodless operating field necessitates complete circulatory arrest during short period of time to enable the surgeon to optimally remove the clot materials located into the pulmonary arteries.

To protect the brain and avoid irreversible brain injury during circulatory arrest(s), body temperature is lowered at 18-20°C. Deep hypothermia can lead to significant arterial vasoconstriction, which can reduce the blood supply to the brai. It also increases the solubility of CO2 in the blood, leading to respiratory alkalosis, which can also lead to vasoconstriction of cerebral vessels, increasing the risk of ischemic lesions.

In adult there is no consistent data on the cerebral perfusion during PAE surgery under deep hypothermia at 18-20°C. Animal studies showed that cerebral regulation seems to be preserved under these conditions. A better understanding of the effect of deep hypothermia on cerebral perfusion during PAE surgery is essential to adapt our management to limit the occurrence of postoperative neurological complications.

Recruitment information / eligibility

• Status: Recruiting
• Enrollment: 80
• Est. completion date: May 24, 2025
• Est. primary completion date: February 24, 2025
• Accepts healthy volunteers: No
• Gender: All
• Age group: 18 Years and older

Eligibility

Inclusion Criteria:

• Scheduled for pulmonary artery thromboendarterectomy surgery.

• Patient with free, written and informed consent.

• Patient affiliated to a social security scheme (beneficiary or beneficiary's beneficiary).

• French-speaking patient.

Exclusion Criteria:

• Patient refusing to participate in the study.

• Patient under guardianship.

• Patient deprived of liberty.

• Pregnant or breast-feeding women.

Related Conditions & MeSH terms

• Cerebral Perfusion
• Hypertension, Pulmonary
• Hypothermia
• Pulmonary Hypertension

Intervention

Procedure:
• Bilateral trans-cranial Doppler ultrasound
Velocity measurements in the middle cerebral artery are made using an ultrasound probe applied to the patient's temple during surgery.

Locations

Country	Name	City	State
France	Hôpital Marie Lannelongue	Le Plessis-Robinson

Sponsors (1)

Lead Sponsor	Collaborator
Fondation Hôpital Saint-Joseph

Country where clinical trial is conducted

France, 

References & Publications (2)

Brown CH 4th, Neufeld KJ, Tian J, Probert J, LaFlam A, Max L, Hori D, Nomura Y, Mandal K, Brady K, Hogue CW; Cerebral Autoregulation Study Group; Shah A, Zehr K, Cameron D, Conte J, Bienvenu OJ, Gottesman R, Yamaguchi A, Kraut M. Effect of Targeting Mean Arterial Pressure During Cardiopulmonary Bypass by Monitoring Cerebral Autoregulation on Postsurgical Delirium Among Older Patients: A Nested Randomized Clinical Trial. JAMA Surg. 2019 Sep 1;154(9):819-826. doi: 10.1001/jamasurg.2019.1163. — View Citation

Liu Y, Chen K, Mei W. Neurological complications after cardiac surgery: anesthetic considerations based on outcome evidence. Curr Opin Anaesthesiol. 2019 Oct;32(5):563-567. doi: 10.1097/ACO.0000000000000755. — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Assessment of cerebral blood perfusion during deep hypothermia	Cerebral blood perfusion during deep hypothermia (18-20°C) will be assessed by measuring mean blood flow velocities in the middle cerebral arteries (MCAs) using trans-cranial Doppler ultrasound (DTC) at different time of the surgery (Four measures in total). All measure are performed during the time of the surgery. The first measure (M1) is baseline to which the other measure will be compared to.	M1: Baseline-normothermia after induction of general anesthesia (H0) M2: During CPB-at 18°C-before cardiac arrest (H2) M3: After cardiac arrest-at 18°C before (H4) M4: End of surgery-normothermia (H6)
Secondary	Correlation between NIRS and middle cerebral arteries velocity values for each measure.	For each measure of middle cerebral arteries blood flow velocity performed during the surgery, the value of the near infrared spectroscopy (NIRS) is recorded. A total of four measures is performed during the time of the surgery.	M1: Baseline-normothermia after induction of general anesthesia (H0) M2: During CPB-at 18°C-before cardiac arrest (H2) M3: After cardiac arrest-at 18°C before (H4) M4: End of surgery-normothermia (H6)
Secondary	Seek for post-circulatory arrest hyperemia	Comparison of the middle cerebral arteries blood flow velocities during the period of hypothermia, before and after cardiac arrest.	M2: During CPB after cooling at 18°C before cardiac arrest (H2). M3: After cardiac arrest at 18°C before rewarming period (H4).